We propose to explore the functional properties of organotypic explants of cerebellum derived from neurological mutants of the mouse. Tissue cultures will be derived from animals at birth including the mutants commonly described as reeler, weaver, staggerer, and jimpy. Initially, the correspondence between the known anomalies that develop in vivo and those elaborated in vitro will be established. Subsequently, the functional correlates of the probable in vitro mutant derangements will be explored in electrophysiological experiments. Progressive developmental changes in patterns of spontaneous activity and stimulus provoked synaptic activation will be examined using extracellular microelectrode recording techniques. Comparisons will also be made with electrophysiological data derived from cerebellar recordings from in vivo preparations. Exploratory experiments involving intracellular recordings from Purkinje cells of mutant and non-mutant explants will be performed. These experiments will be coupled with efforts to employ currently available intracellular dye techniques. Lastly, the processes of cell migration in organotypic cultures of mutant mice cerebellum will be examined in exploratory studies using radioautographic procedures.